package PTA.javabianchengjichu2;

import java.util.Scanner;
enum Score {
    A,B,C,D,E;
        }
public class ex28 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int score = sc.nextInt();
        if(score<60){
            System.out.println(Score.E);
        }else if(score>=60&&score<70){
            System.out.println(Score.D);
        }else if(score>=70&&score<80) {
            System.out.println(Score.C);
        }else if(score>=80&&score<90){
            System.out.println(Score.B);
        }else{
            System.out.println(Score.A);
        }
    }
}
